Battery and battery manufacturing method

Abstract

This battery 1 has a charging / discharging body 10 including electrodes (positive electrode 11 and negative electrode 12) provided with electrode tabs (positive electrode tab 11b and negative electrode tab 12b), and a current collector 20 (positive electrode current collector plate 21 and negative electrode current collector plate 22) bonded to the electrode tabs (positive electrode tab 11b and negative electrode tab 12b). The current collector 20 (positive electrode current collector plate 21 and negative electrode current collector plate 22) is provided with convex bonding portions (positive electrode bonding portion 21f and negative electrode bonding portion 22f). The electrode tabs (positive electrode tab 11b and negative electrode tab 12b) and the bonding portions (positive electrode bonding portion 21f and negative electrode bonding portion 22f) are welded.

Description

[Technical Field]

[0001] The present invention relates to a battery and a method for manufacturing the battery. [Background technology]

[0002] Conventionally, in batteries, electrical conduction has been achieved by joining the electrode tabs of the charge / discharge body and the current collector together (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-039713 Summary of the Invention [Problem to be solved by the invention]

[0004] In batteries, there is a demand for improved conductivity between the electrode tabs of the charge / discharge body and the current collector. [Means for solving the problem]

[0005] To solve the problems of the prior art described above, the battery of the present invention includes a charge / discharge body including an electrode with an electrode tab, and a current collector joined to the electrode tab. The current collector has a convex joint portion. The electrode tab and the joint portion are welded to each other.

[0006] In addition, in order to solve the problems of the conventional technology described above, the manufacturing method of the battery of the present invention includes a first step of contacting the electrode tab with the joint portion, and a second step of welding the electrode tab with the current collector. [Effects of the Invention]

[0007] The battery of the present invention can improve the conductivity between the electrode tab and the current collector, and the battery manufacturing method of the present invention can reduce welding defects between the electrode tab and the current collector, thereby improving the productivity and yield of the battery. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a perspective view showing a battery 1 of a first embodiment. [Figure 2] FIG. 2 is a cross-sectional perspective view showing the periphery of a negative electrode terminal 42 of the battery 1 according to the first embodiment. [Figure 3] FIG. 2 is a cross-sectional view showing the periphery of a negative electrode terminal 42 of the battery 1 according to the first embodiment. [Figure 4] FIG. 2 is a cross-sectional perspective view showing the periphery of a positive electrode terminal 41 of the battery 1 according to the first embodiment. [Figure 5] FIG. 2 is a cross-sectional view showing the periphery of a positive electrode terminal 41 of the battery 1 according to the first embodiment. [Figure 6] 1 is an exploded perspective view showing a battery 1 according to a first embodiment. [Figure 7] 1 is a perspective view showing the charging / discharging unit 10 of the battery 1 of the first embodiment, with a portion of the charging / discharging unit 10 including a positive electrode tab 11b and a negative electrode tab 12b extracted from the charging / discharging unit 10 and shown at the bottom. [Figure 8] 1 is a cross-sectional view showing a part of a charging / discharging body 10 of a battery 1 according to a first embodiment. [Figure 9] FIG. 4 is a cross-sectional view showing a part of a charging / discharging body 110 of a modified example of the battery 1 of the first embodiment. [Figure 10] 3 is a perspective view showing the periphery of the negative electrode current collector plate 22 and the negative electrode tab 12b of the battery 1 of the first embodiment. FIG. [Figure 11] 2 is a perspective view showing the periphery of the positive electrode current collector plate 21 and the positive electrode tab 11b of the battery 1 of the first embodiment. FIG. [Figure 12] 3 is a cross-sectional view showing a positive electrode joint portion 21f of a positive electrode current collector plate 21 of the battery 1 of the first embodiment. FIG. [Figure 13] 10 is a cross-sectional view showing a joint 23f of a positive electrode current collector plate 23 of a battery 1 according to a first modification of the first embodiment. FIG. [Figure 14] 10 is a cross-sectional view showing a joint 24f of a positive current collector plate 24 of a battery 1 according to a second modification of the first embodiment. FIG. [Figure 15] 10 is a cross-sectional view showing a joint 25f of a positive current collector plate 25 of a battery 1 according to a third modification of the first embodiment. FIG. [Figure 16] FIG. 2 is an exploded perspective view showing the periphery of a negative electrode terminal 42 of the battery 1 according to the first embodiment. [Figure 17] FIG. 2 is an exploded perspective view showing the lid 52 and sealing plug 53 of the battery 1 of the first embodiment. [Figure 18] FIG. 2 is an exploded perspective view showing the periphery of a positive electrode terminal 41 of the battery 1 according to the first embodiment. [Figure 19] 3 is a perspective view showing the periphery of a negative electrode current collector plate 22 in the manufacture of the battery 1 of the first embodiment. FIG. [Figure 20] 3 is a perspective view showing the negative electrode current collector plate 22 and the negative electrode tab 12b before joining in the manufacturing process of the battery 1 according to the first embodiment. FIG. [Figure 21] 10 is a perspective view showing the negative electrode current collector plate 22 and the negative electrode tab 12b being joined together in the manufacturing process of the battery 1 according to the first embodiment. FIG. [Figure 22] FIG. 4 is a perspective view showing a part of a battery 2 according to a second embodiment. [Figure 23] FIG. 10 is a perspective view showing the periphery of the negative electrode current collector plate 22 and the negative electrode tab 212b of the battery 2 of the second embodiment. [Figure 24] FIG. 10 is a perspective view showing a part of a battery 3 according to a third embodiment. [Figure 25] FIG. 10 is a perspective view showing the periphery of the negative electrode current collector plate 22 and the negative electrode tab 312b of the battery 3 of the third embodiment. [Figure 26] FIG. 10 is a perspective view showing a part of a battery 4 according to a fourth embodiment. [Figure 27] FIG. 10 is a perspective view showing the periphery of a negative electrode current collector plate 122 and a negative electrode tab 412b of a battery 4 according to a fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] Each embodiment of the present invention will be described with reference to the drawings. To facilitate understanding of each embodiment, the size and proportions of components may be exaggerated in the drawings. In the drawings, the electrode tabs of the charge / discharge device are shown shorter than their actual length. The electrodes in FIGS. 10, 11, 23, 25, and 27 are shown convexly deformed along the joints of the current collector plates. When the electrodes are welded to the joints of the current collector plates, they deform convexly along the joints of the current collector plates. However, after welding to the joints of the current collector plates, the portions of the electrodes other than those welded to the joints of the current collector plates may sag due to their own weight, eliminating the convex deformation. The number of electrode tabs shown in FIGS. 23, 25, and 27 is reduced compared to the corresponding electrode tabs shown in FIGS. 22, 24, and 26. In each embodiment, the same components are designated by the same reference numerals, and redundant description will be omitted. In each embodiment, a left-handed XYZ Cartesian coordinate system is used, with the X, Y, and Z axes as its coordinate axes. The arrows on each of the X, Y, and Z axes indicate the positive direction of the coordinate axis. The X axis is the coordinate axis in the longitudinal direction of the rectangular parallelepiped battery. The Y axis is the coordinate axis in the lateral direction of the battery. The Z axis is the coordinate axis in the height direction of the battery. The plane formed by the X and Y axes is called the XY plane, the plane formed by the Y and Z axes is called the YZ plane, and the plane formed by the X and Z axes is called the XZ plane. However, the positional relationships expressed in the XYZ Cartesian coordinate system are merely relative positional relationships.

[0010] [First embodiment] (Configuration of Battery 1 of First Embodiment) The configuration of the battery 1 will be described with reference to FIGS.

[0011] 1 to 5, the battery 1 includes a charging / discharging body 10 that charges and discharges electricity, a current collector 20 connected to the charging / discharging body 10, a current interrupter 30 connected to the current collector 20, an external terminal 40 connected to the current collector 20 or the current interrupter 30, and an exterior body 50 that houses or attaches the components of the battery 1. The battery 1 also includes an insulator 60 that insulates the components of the battery 1 from the exterior body 50, and a sealing body 70 that seals the components of the battery 1 from the exterior body 50.

[0012] The charge / discharge unit 10 charges and discharges electricity. The charge / discharge unit 10 shown in Figs. 2 to 8 includes a positive electrode 11, a negative electrode 12, a separator 13 (insulating member), and an electrolyte 14. The electrodes (positive electrode 11 and negative electrode 12) are equipped with electrode tabs (positive electrode tab 11b and negative electrode tab 12b). As shown in Fig. 7, the charge / discharge unit 10 is configured by winding components, in which the positive electrode 11, separator 13, negative electrode 12, and separator 13 are stacked in this order, into a rectangular parallelepiped shape.

[0013] 7 and 8, the positive electrode 11 includes a long positive electrode current collecting layer 11S and a positive electrode active material layer 11T bonded to the positive electrode current collecting layer 11S. The positive electrode current collecting layer 11S includes a current collecting portion 11a and a positive electrode tab 11b. The positive electrode active material layer 11T is bonded to the current collecting portion 11a. The positive electrode active material layer 11T faces, for example, the entire area of ​​the current collecting portion 11a along the short side direction (Z-axis direction).

[0014] As shown in Figures 7 and 8, the positive electrode tab 11b protrudes in the short direction of the current collecting portion 11a from a side edge 11c along the longitudinal direction of the current collecting portion 11a. The positive electrode tab 11b is formed integrally with the current collecting portion 11a. One positive electrode tab 11b is formed for each current collecting portion 11a. The current collecting portion 11a is formed of, for example, aluminum or an aluminum alloy.

[0015] The positive electrode active material layer 11T contains a positive electrode active material made of a lithium-containing composite oxide, a binder, a conductive additive, etc. The lithium-containing composite oxide contains, for example, a metal element such as nickel (Ni), cobalt (Co), or manganese (Mn), and lithium (Li).

[0016] As shown in FIGS. 7 and 8, the negative electrode 12 includes a long negative electrode current collecting layer 12S and a negative electrode active material layer 12T bonded to the negative electrode current collecting layer 12S. The negative electrode current collecting layer 12S includes a current collecting portion 12a and a negative electrode tab 12b. The current collecting portion 12a of the negative electrode 12 has a width along the short side direction (Z-axis direction) greater than that of the current collecting portion 11a of the positive electrode 11. Both ends of the current collecting portion 11a of the positive electrode 11 along the short side direction are located within the range along the short side direction of the current collecting portion 12a of the negative electrode 12, with a separator 13 interposed between them. The negative electrode active material layer 12T is bonded to the current collecting portion 12a. The negative electrode active material layer 12T faces, for example, the entire area along the short side direction of the current collecting portion 12a.

[0017] As shown in Figures 7 and 8, for example, the negative electrode tab 12b protrudes in the short direction of the current collecting part 12a from a side edge 12c along the longitudinal direction of the current collecting part 12a. When stacked with the positive electrode 11 via the separator 13, the negative electrode tab 12b protrudes in the same direction as the positive electrode tab 11b of the positive electrode 11. When stacked with the positive electrode 11 via the separator 13, the negative electrode tab 12b is separated from the positive electrode tab 11b of the positive electrode 11. The negative electrode tab 12b is formed integrally with the current collecting part 12a. One negative electrode tab 12b is formed for each current collecting part 12a. The current collecting part 12a is formed from, for example, copper or a copper alloy.

[0018] The negative electrode active material layer 12T contains a negative electrode active material made of a carbon-based material, a binder, a conductive additive, etc. The carbon-based material is, for example, graphite.

[0019] As shown in FIGS. 7 and 8, the separator 13 (insulator) insulates the positive electrode 11 from the negative electrode 12 while allowing lithium ions to pass through. The separator 13 is formed in an elongated shape. The separator 13 has a width along its short side (Z-axis direction) greater than that of the current collector 11a of the positive electrode 11 and the current collector 12a of the negative electrode 12. Both ends of the current collector 11a of the positive electrode 11 along the short side are located within the short side of the separator 13, and both ends of the current collector 12a of the negative electrode 12 along the short side are located within the short side of the separator 13. The separator 13 is made of a porous material. Polyethylene (PE) or polypropylene (PP) is used for the separator 13. A heat-resistant insulating material may be used instead of the separator 13. The heat-resistant insulating material may be, for example, ceramic. This configuration is known as a separator-less configuration.

[0020] The electrolyte 14 corresponds to a so-called electrolytic solution. The electrolyte 14 contains an organic solvent, a supporting salt, and an additive. The organic solvent may be, for example, a carbonate ester. The supporting salt may be, for example, a lithium salt.

[0021] A charge / discharge body 110, which is a modified example of the charge / discharge body 10, will be described with reference to FIG. 9. The charge / discharge body 110 differs in the configuration of the positive electrode 111 from the configuration of the positive electrode 11 of the first embodiment. In the configuration of the charge / discharge body 110, the same components as those of the charge / discharge body 10 are given the same reference numerals, and their description will be omitted. The positive electrode active material layer 111T of the charge / discharge body 110 faces the current collecting part 11a except for both ends along the short side direction (Z-axis direction). The heat-resistant insulating layer 111U of the charge / discharge body 110 is bonded to both ends along the short side direction of the current collecting part 11a and to the base end portion of the positive electrode tab 11b. The heat-resistant insulating layer 111U contains, for example, ceramics.

[0022] The current collector 20 is connected to the positive electrode tab 11b and the negative electrode tab 12b of the charge / discharge body 10. The current collector 20 shown in Figures 2 to 5, 10 to 12, 16 and 18 includes a positive electrode current collector plate 21 and a negative electrode current collector plate 22.

[0023] As shown in FIGS. 4 and 5, the positive current collector plate 21 electrically connects the positive electrode tab 11b of the charge / discharge unit 10 to the positive electrode terminal 41 via the current interrupter 30. As shown in FIG. 18, the positive current collector plate 21 includes a first base portion 21a having a rectangular parallelepiped plate shape, a second base portion 21b having a rectangular parallelepiped plate shape, and a connecting portion 21c that connects the first base portion 21a and the second base portion 21b in a stepped manner with different heights. A recess 21d is formed on the upper surface (the surface facing the positive Z-axis direction) of the second base portion 21b, reducing the thickness of the second base portion 21b. A weak portion 21e, which is a ring-shaped recess, is formed in the center of the recess 21d. A convex positive electrode joint portion 21f that protrudes downward (in the negative Z-axis direction) is formed on the first base portion 21a. The positive electrode joint portion 21f is formed in a triangular shape. The positive electrode joint 21f faces the charge / discharge body 10 and extends in the longitudinal direction (X-axis direction) of the charge / discharge body 10. The positive electrode joint 21f has higher rigidity than the positive electrode tab 11b in the stacking direction (Z-axis direction) of the positive electrode tab 11b and the positive electrode current collector plate 21. The tip of the positive electrode joint 21f is welded to the positive electrode tab 11b. When the positive electrode tab 11b is welded to the positive electrode joint 21f, it is pressed toward the positive electrode joint 21f, and is thereby deformed to fit along the convex positive electrode joint 21f. The positive electrode current collector plate 21 is formed of, for example, aluminum or an aluminum alloy.

[0024] As shown in FIGS. 2 and 3, for example, the negative electrode current collector plate 22 electrically connects the negative electrode tab 12b of the charge / discharge body 10 and the negative electrode terminal 42. As shown in FIG. 16, for example, the negative electrode current collector plate 22 includes a rectangular parallelepiped base 22a and an insertion hole 22b penetrating the base 22a. The insertion hole 22b of the negative electrode current collector plate 22 receives the insertion portion 42b of the negative electrode terminal 42. A convex negative electrode joint 22f that protrudes downward (in the negative Z-axis direction) is formed on the base 22a. The negative electrode joint 22f is formed in a triangular shape. The negative electrode joint 22f faces the charge / discharge body 10 and extends in the longitudinal direction (X-axis direction) of the charge / discharge body 10. The negative electrode joint 22f has higher rigidity than the negative electrode tab 12b in the stacking direction (Z-axis direction) of the negative electrode tab 12b and the negative electrode current collector plate 22. The tip of the negative electrode joint portion 22f is welded to the negative electrode tab 12b. When the negative electrode tab 12b is welded to the negative electrode joint portion 22f, it is pressed toward the negative electrode joint portion 22f, and is thereby deformed so as to fit the convex negative electrode joint portion 22f. The negative electrode current collector plate 22 is made of, for example, copper or a copper alloy.

[0025] The current interrupter 30 is connected to the current collector 20, and provides electrical continuity between the current collector 20 and the positive electrode terminal 41. The current interrupter 30 shown in FIGS. 4, 5, and 18 includes a diaphragm 31, a conductive member 32, and a pair of support bases 33.

[0026] 18, the diaphragm 31 includes a curved cylindrical main body 31a, a disk-shaped first joint portion 31b provided at the tip end side (negative side of the Z axis) of the main body 31a, and a ring-shaped second joint portion 31c provided at the base end side (positive side of the Z axis) of the main body 31a. The first joint portion 31b is joined to a recess 21d of the positive current collector plate 21. The second joint portion 31c is joined to a conductive member 32. The diaphragm 31 is formed of, for example, aluminum or an aluminum alloy.

[0027] 18, the conductive member 32 is formed in a cylindrical shape. A positive electrode-side first insulating plate 62 is joined to the upper surface (the surface on the positive Z-axis direction side) of the conductive member 32. A second joint portion 31c of the diaphragm 31 is joined to the periphery of the lower surface (the surface on the negative Z-axis direction side) of the conductive member 32. The conductive member 32 is formed of, for example, aluminum or an aluminum alloy.

[0028] As shown in Fig. 18, for example, the support base 33 includes a rectangular parallelepiped main body 33a extending in the short-side direction (Y-axis direction) of the battery 1, and leg portions 33b extending downward (in the negative Z-axis direction) from both sides of the main body 33a in the longitudinal direction (Y-axis direction). One support base 33 is provided on each end of the diaphragm 31 along the longitudinal direction (X-axis direction) of the battery 1. The main body 33a is attached to the positive electrode side first insulating plate 62. The leg portions 33b are attached to the second base portion 21b of the positive electrode current collector plate 21. The support base 33 is formed, for example, from insulating resin.

[0029] The external terminal 40 is connected to the current collector 20 or the current interrupter 30. The external terminal 40 shown in Figures 1 to 6, 10, 16 and 18 includes a positive electrode terminal 41 and a negative electrode terminal 42.

[0030] The positive electrode terminal 41 is connected to the conductive member 32 of the current interrupter 30, as shown in Fig. 5, for example. As shown in Fig. 18, for example, the positive electrode terminal 41 includes a rectangular parallelepiped plate-shaped base 41a, a cylindrical insertion portion 41b protruding downward (in the negative Z-axis direction) from the base 41a, and a cylindrical joint portion 41c protruding downward (in the negative Z-axis direction) from the periphery of the base 41a.

[0031] 18 , the base 41a is in contact with the base 64a of the positive electrode-side second insulating plate 64. The insertion portion 41b is inserted into the insertion hole 64b of the positive electrode-side second insulating plate 64, the positive electrode-side insertion hole 52a of the lid 52, the insertion hole 62b of the positive electrode-side first insulating plate 62, and the insertion hole 32b of the conductive member 32.

[0032] 18, the joint portion 41c protrudes downward (in the negative direction of the Z axis) from the insertion hole 32b of the conductive member 32 and is expanded radially outward to be joined to the conductive member 32. That is, the joint portion 41c is crimped to the periphery of the insertion hole 32b of the conductive member 32. Furthermore, the joint portion 41c is welded to the periphery of the insertion hole 32b of the conductive member 32. The positive electrode terminal 41 is formed of, for example, aluminum or an aluminum alloy.

[0033] The negative electrode terminal 42 is connected to the negative electrode current collector plate 22, as shown in Fig. 3, for example. As shown in Fig. 16, for example, the negative electrode terminal 42 includes a rectangular parallelepiped plate-shaped base 42a, a cylindrical insertion portion 42b protruding downward (in the negative Z-axis direction) from the base 42a, and a cylindrical joint portion 42c protruding downward (in the negative Z-axis direction) from the periphery of the base 42a.

[0034] 16 , the base 42a is in contact with the base 65a of the negative electrode side second insulating plate 65. The insertion portion 42b is inserted into the insertion hole 65b of the negative electrode side second insulating plate 65, the negative electrode side insertion hole 52b of the lid 52, the insertion hole 63b of the negative electrode side first insulating plate 63, and the insertion hole 22b of the negative electrode current collector plate 22.

[0035] 16, the joint portion 42c protrudes downward from the insertion hole 22b of the negative current collector plate 22 and is expanded radially outward to be joined to the negative current collector plate 22. That is, the joint portion 42c is crimped to the periphery of the insertion hole 22b of the negative current collector plate 22. Furthermore, the joint portion 42c is welded to the periphery of the insertion hole 22b of the negative current collector plate 22. The negative terminal 42 is formed of, for example, copper or a copper alloy.

[0036] The components of the battery 1 are housed or attached in the exterior body 50. The exterior body 50 shown in Figures 1 to 6, 10, 11, and 16 to 18 includes a container 51, a lid 52, and a sealing plug 53.

[0037] 2 and 6, the container 51 contains the charge / discharge unit 10 covered with an insulating cover 61 and the like. The container 51 is made of a rectangular metal can. As shown in FIG. 6, the container 51 includes an opening 51a that opens along the longitudinal direction and a container portion 51b that is continuous with the opening 51a. The container 51 is made of, for example, aluminum or an aluminum alloy.

[0038] The lid 52 seals the opening 51a of the container 51, as shown in, for example, FIGS. 2 and 6. The lid 52 faces one side 10a (side) of the charge / discharge body 10, where the positive electrode 11, the separator 13, and the negative electrode 12 are adjacent to each other. The lid 52 is formed of a long, plate-shaped metal plate. The lid 52 has a positive electrode side insertion hole 52a formed as a circular through-hole at one end in the longitudinal direction. The insertion portion 41b of the positive electrode terminal 41 is inserted into the positive electrode side insertion hole 52a. The lid 52 has a negative electrode side insertion hole 52b formed as a circular through-hole at the other end in the longitudinal direction. The insertion portion 42b of the negative electrode terminal 42 is inserted into the negative electrode side insertion hole 52b.

[0039] The lid 52 has a liquid inlet 52c formed as a circular through-hole between the positive electrode side insertion hole 52a and the negative electrode side insertion hole 52b. The electrolyte 14 is injected from the lid 52 toward the container 51 through the liquid inlet 52c. An insertion portion 53b of a sealing plug 53 is inserted into the liquid inlet 52c. A split valve 52d is formed in the center of the lid 52 in the longitudinal direction. The lid 52 is welded to the container 51. The lid 52 is made of, for example, aluminum or an aluminum alloy.

[0040] 17, the sealing plug 53 seals the liquid inlet hole 52c of the lid 52. The sealing plug 53 is formed in a cylindrical shape. The sealing plug 53 includes a head portion 53a having a relatively large outer diameter and an insertion portion 53b that is continuous with the head portion 53a and has a relatively small outer diameter. The head portion 53a of the sealing plug 53 is welded to the lid 52. The sealing plug 53 is formed of, for example, aluminum or an aluminum alloy.

[0041] The insulator 60 insulates the components of the battery 1 from the exterior body 50. The insulator 60 shown in Figures 2 to 6, 10, 11, 16, and 18 includes an insulating cover 61, a positive electrode-side first insulating plate 62, a negative electrode-side first insulating plate 63, a positive electrode-side second insulating plate 64, and a negative electrode-side second insulating plate 65.

[0042] As shown in FIG. 6, the insulating cover 61 covers and insulates the charging / discharging unit 10. The insulating cover 61 includes a pair of opposing side surfaces (a first side surface 61a and a second side surface 61b) and an opening 61c between the first side surface 61a and the second side surface 61b, exposing one side portion 10a of the charging / discharging unit 10. The insulating cover 61 covers all but one side of the one side portion 10a of the charging / discharging unit 10. That is, the insulating cover 61 covers the other side portion 10b opposite the one side portion 10a of the charging / discharging unit 10, and the outer periphery portion 10c located between the one side portion 10a and the other side portion 10b of the charging / discharging unit 10. The insulating cover 61 is formed into a pentahedron shape by folding a polyhedron-shaped sheet into a box shape. The insulating cover 61 is made of, for example, polypropylene.

[0043] As shown in FIG. 5, for example, the positive electrode side first insulating plate 62 insulates the positive electrode current collector plate 21 and the conductive member 32 from the lid 52. As shown in FIG. 18, for example, the positive electrode side first insulating plate 62 includes a rectangular parallelepiped base 62a, an insertion hole 62b penetrating the base 62a, and a protrusion 62c annularly extending from the side edge of the base 62a and protruding in a direction away from the surrounding lid 52. The positive electrode side first insulating plate 62 accommodates the positive electrode current collector plate 21, the conductive member 32, etc. in a space defined by the base 62a and the protrusion 62c. The insertion portion 41b of the positive electrode terminal 41 is inserted into the insertion hole 62b. The positive electrode side first insulating plate 62 is formed, for example, from insulating resin.

[0044] As shown in FIG. 3, for example, the negative electrode side first insulating plate 63 insulates the negative electrode current collector plate 22 from the lid 52. As shown in FIG. 16, for example, the negative electrode side first insulating plate 63 includes a rectangular parallelepiped base 63a, an insertion hole 63b penetrating the base 63a, and a protrusion 63c annularly extending from the side edge of the base 63a and protruding in a direction away from the surrounding lid 52. The negative electrode side first insulating plate 63 accommodates the negative electrode current collector plate 22 in a space defined by the base 63a and the protrusion 63c. The insertion portion 42b of the negative electrode terminal 42 is inserted into the insertion hole 63b. The negative electrode side first insulating plate 63 is formed of, for example, insulating resin.

[0045] The positive electrode side second insulating plate 64 insulates the positive electrode terminal 41 from the lid 52, as shown in FIG. 5, for example. As shown in FIG. 18, for example, the positive electrode side second insulating plate 64 includes a rectangular parallelepiped base 64a, an insertion hole 64b penetrating the base 64a, and a protrusion 64c annularly extending from the side edge of the base 64a and protruding in a direction away from the surrounding lid 52. The positive electrode side second insulating plate 64 accommodates the positive electrode terminal 41 in a space defined by the base 64a and the protrusion 64c. The insertion portion 41b of the positive electrode terminal 41 is inserted into the insertion hole 64b. The positive electrode side second insulating plate 64 is formed, for example, from insulating resin.

[0046] As shown in FIG. 3, for example, the negative electrode side second insulating plate 65 insulates the negative electrode terminal 42 from the lid 52. As shown in FIG. 16, for example, the negative electrode side second insulating plate 65 includes a rectangular parallelepiped base 65a, an insertion hole 65b penetrating the base 65a, and a protrusion 65c annularly extending from the side edge of the base 65a and protruding in a direction away from the surrounding lid 52. The negative electrode side second insulating plate 65 accommodates the negative electrode terminal 42 in a space defined by the base 65a and the protrusion 65c. The insertion portion 42b of the negative electrode terminal 42 is inserted into the insertion hole 65b. The negative electrode side second insulating plate 65 is formed of, for example, insulating resin.

[0047] The sealing body 70 seals the components of the battery 1 and the exterior body 50. The sealing body 70 shown in Figures 2 to 5, 16 and 18 includes a positive electrode side gasket 71 and a negative electrode side gasket 72.

[0048] As shown in FIG. 5, for example, the positive electrode side gasket 71 insulates the positive electrode side second insulating plate 64 from the lid 52. The positive electrode side gasket 71 is formed in a cylindrical shape. As shown in FIG. 18, for example, the positive electrode side gasket 71 includes a first insertion portion 71a having a relatively large outer diameter, a second insertion portion 71b continuous with the first insertion portion 71a and having a relatively small outer diameter, and an insertion hole 71c passing through the first insertion portion 71a and the second insertion portion 71b. The first insertion portion 71a of the positive electrode side gasket 71 is inserted into the insertion hole 64b of the positive electrode side second insulating plate 64. The second insertion portion 71b of the positive electrode side gasket 71 is inserted into the positive electrode side insertion hole 52a of the lid 52. The insertion portion 41b of the positive electrode terminal 41 is inserted into the insertion hole 71c. The positive electrode side gasket 71 is formed, for example, from rubber having insulating properties and elasticity.

[0049] As shown in FIG. 3 , the negative electrode side gasket 72 insulates the negative electrode side second insulating plate 65 from the lid 52. The negative electrode side gasket 72 is formed in a cylindrical shape. As shown in FIG. 16 , the negative electrode side gasket 72 includes a first insertion portion 72a with a relatively large outer diameter, a second insertion portion 72b that is continuous with the first insertion portion 72a and has a relatively small outer diameter, and an insertion hole 72c that passes through the first insertion portion 72a and the second insertion portion 72b. The first insertion portion 72a of the negative electrode side gasket 72 is inserted into the insertion hole 65b of the negative electrode side second insulating plate 65. The second insertion portion 72b of the negative electrode side gasket 72 is inserted into the negative electrode side insertion hole 52b of the lid 52. The insertion portion 42b of the negative electrode terminal 42 is inserted into the insertion hole 72c. The negative electrode side gasket 72 is formed, for example, from rubber that has insulating properties and elasticity.

[0050] (Method for manufacturing battery 1 of the first embodiment) A manufacturing method of the battery 1 will be described with reference to FIGS. 19 to 21. In the description of the manufacturing method of the battery 1 of the first embodiment, only the manufacturing steps specific to the battery 1 will be described, and a description of the manufacturing steps similar to those of a general battery will be omitted. Specifically, the manufacturing method of the battery 1 will be described as a manufacturing method for welding an electrode tab (negative electrode tab 12b) to a current collector plate (negative electrode current collector plate 22). The manufacturing method for welding the positive electrode tab 11b to the positive electrode current collector plate 21 is the same as the manufacturing method for welding the negative electrode tab 12b to the negative electrode current collector plate 22, and therefore a description thereof will be omitted.

[0051] The manufacturing method specific to battery 1 includes a first step of contacting negative electrode tab 12b and negative electrode current collector plate 22 shown in Figures 19 to 21, and a second step of welding negative electrode tab 12b and negative electrode current collector plate 22 shown in Figure 21.

[0052] As shown in FIGS. 19 to 21 , in the first step, the negative electrode tab 12b is brought into contact with the negative electrode current collector plate 22. In the first step, the negative electrode tab 12b is brought close to the negative electrode current collector plate 22 from the negative Z-axis direction, and the negative electrode tab 12b is brought into contact with the negative electrode joint portion 22f of the negative electrode current collector plate 22. Here, in the first step, a pair of pressing members (a first pressing member 501 and a second pressing member 502) are used to press the negative electrode tab 12b and both end sides of the negative electrode joint portion 22f of the negative electrode current collector plate 22 against each other. The first pressing member 501 and the second pressing member 502 are each formed in a rectangular parallelepiped shape and have sufficient rigidity. Specifically, the first pressing member 501 and the second pressing member 502 are formed, for example, from metal blocks. When the first pressing member 501 and the second pressing member 502 press the negative electrode tab 12b and both ends of the negative electrode joint portion 22f of the negative electrode current collector plate 22 against each other, the negative electrode tab 12b is pulled toward both ends of the negative electrode joint portion 22f. That is, when the negative electrode tab 12b is pressed along both ends of the negative electrode joint portion 22f (both ends in the Y-axis direction) while in contact with the negative electrode joint portion 22f, tension is applied to the negative electrode tab 12b in both the positive and negative directions of the Y-axis centered on the negative electrode joint portion 22f. As a result, the negative electrode tab 12b is pressed against the negative electrode joint portion 22f. The portion of the negative electrode tab 12b pressed against the negative electrode joint portion 22f is deformed into a convex shape along the shape of the negative electrode joint portion 22f. The negative electrode tab 12b and the negative electrode joint portion 22f of the negative electrode current collector plate 22 come into close contact with each other.

[0053] As shown in FIG. 21 , in the second step, the negative electrode tab 12b and the negative current collector plate 22 are welded together. In the second step, while maintaining the pressure of the negative electrode tab 12b against the negative electrode joint portion 22f of the negative current collector plate 22 in the first step, the negative electrode tab 12b and the negative electrode joint portion 22f of the negative current collector plate 22 are welded together with a laser beam L1. The negative electrode joint portion 22f extends along the longitudinal direction (X-axis direction) of the battery 1. Therefore, in the second step, the laser beam L1 is scanned in the X-axis direction to continuously weld the negative electrode tab 12b and the negative electrode joint portion 22f of the negative current collector plate 22 in a linear manner. Note that in the second step, the laser beam L1 may be scanned in the X-axis direction to intermittently weld the negative electrode tab 12b and the negative electrode joint portion 22f of the negative current collector plate 22. Thereafter, in a second step, the first pressing member 501 and the second pressing member 502 are retracted from the negative electrode tab 12b.

[0054] (Effects of the Battery 1 and the Manufacturing Method of the Battery 1 of the First Embodiment) The following describes the effects of the battery 1 and the manufacturing method for the battery 1. The following mainly describes the effects related to the welding of the positive electrode tab 11b and the positive electrode current collector plate 21. The effects related to the welding of the positive electrode tab 11b and the positive electrode current collector plate 21 and the effects related to the welding of the negative electrode tab 12b and the negative electrode current collector plate 22 are similar.

[0055] In the battery 1, the electrode tabs (positive electrode tab 11b and negative electrode tab 12b) are welded to the convex joints (positive electrode joint 21f and negative electrode joint 22f) of the current collector 20 (positive electrode current collector 21 and negative electrode current collector 22). In a manufacturing method of the battery 1, the electrode tabs (positive electrode tab 11b and negative electrode tab 12b) are welded to the convex joints (positive electrode joint 21f and negative electrode joint 22f). With this configuration, for example, the positive electrode tab 11b and the positive electrode joint 21f of the positive electrode current collector 21 can be sufficiently welded to each other when they are in sufficient contact with each other. That is, for example, when the positive electrode joint 21f, which is the welding region, protrudes from the positive electrode current collector 21 as in the first embodiment, it is easier to bring the positive electrode tab 11b and the positive electrode joint 21f into intimate contact with each other compared to when the welding region does not protrude from the positive electrode current collector 21 as in the conventional case. Therefore, for example, the positive electrode tab 11b and the positive electrode joint portion 21f can be sufficiently welded to establish electrical continuity. Therefore, in the battery 1, for example, the conductivity between the positive electrode tab 11b and the positive electrode current collector plate 21 can be improved. Furthermore, in the manufacturing method of the battery 1, for example, poor welding between the positive electrode tab 11b and the positive electrode current collector plate 21 can be suppressed, thereby improving the productivity and yield of the battery 1.

[0056] The positive electrode tab 11b, which is deformed convexly along the positive electrode joint portion 21f of the positive current collector plate 21, is welded to the positive electrode joint portion 21f. With this configuration, as shown in FIG. 21 , the positive electrode tab 11b and the positive electrode joint portion 21f are brought into intimate contact with each other along the convex positive electrode joint portion 21f, ensuring a sufficient area for welding between the positive electrode tab 11b and the positive electrode joint portion 21f. That is, the positive electrode tab 11b can be welded in intimate contact with the positive electrode joint portion 21f at any portion of the convex deformed portion. Note that although the positive electrode tab 11b is deformed convexly in FIG. 10 , areas other than the welded area may sag in the negative direction of the Z axis due to its own weight. The positive electrode tab 11b is deformed convexly when welded to the positive electrode joint portion 21f shown in FIG. 21 , but the convex deformation may be eliminated when the battery 1 is positioned upside down as shown in FIG. 1 . That is, the positive electrode tab 11b may hang down in the negative direction of the Z axis after being turned upside down from the state in FIG. 21 to the state in FIG. 1, except for the portion welded to the positive electrode joint portion 21f.

[0057] The positive electrode tab 11b is welded to the tip of the positive electrode joint portion 21f of the positive electrode current collector plate 21. With this configuration, the battery 1 can achieve sufficient electrical continuity between the positive electrode tab 11b and the positive electrode current collector plate 21 with a minimum welding area. Alternatively, the positive electrode tab 11b may be welded to one of two opposing inclined surfaces of the positive electrode joint portion 21f. Alternatively, the positive electrode tab 11b may be welded to the entire surface of the positive electrode joint portion 21f from the base end to the tip facing in the negative Z-axis direction.

[0058] The positive electrode joint portion 21f of the positive electrode current collector plate 21 has higher rigidity than the positive electrode tab 11b in the stacking direction (Z-axis direction) of the positive electrode tab 11b and the positive electrode current collector plate 21. With this configuration, the positive electrode tab 11b can be deformed to conform to the shape of the positive electrode joint portion 21f, and the positive electrode tab 11b can be welded in a state of being in close contact with the positive electrode joint portion 21f. This allows sufficient electrical conduction between the positive electrode tab 11b and the positive electrode current collector plate 21.

[0059] The positive electrode tab 11b and the positive electrode joint portion 21f of the positive electrode current collector plate 21 are welded by laser light L1. Laser welding can be applied to the manufacturing method of the battery 1. In order to sufficiently join the positive electrode tab 11b and the positive electrode joint portion 21f, it is not necessary to join the welded area of ​​the positive electrode tab 11b and the positive electrode joint portion 21f by directly crimping or crimping. That is, in the first embodiment, the joint portion of the positive electrode tab 11b and the positive electrode joint portion 21f can be exposed, allowing laser welding. As such, in the first embodiment, the positive electrode tab 11b and the positive electrode joint portion 21f can be welded by laser welding, which is highly versatile and allows for easy adjustment of welding conditions.

[0060] 8, the positive electrode tab 11b protrudes from the side edge 11c of the positive electrode current collecting layer 11S. With this configuration, the positive electrode tab 11b can be sufficiently welded to the positive electrode joint portion 21f while preventing interference between the positive electrode tab 11b and the positive electrode current collecting layer 11S and the positive electrode active material layer 11T.

[0061] The positive electrode joint portion 21f of the positive electrode current collector plate 21 faces the charge / discharge body 10 and extends in the longitudinal direction (X-axis direction) of the rectangular parallelepiped charge / discharge body 10. With this configuration, a sufficient welding area between the positive electrode tab 11b and the positive electrode joint portion 21f can be secured along the longitudinal direction (X-axis direction) of the charge / discharge body 10.

[0062] The battery 1 includes a conductive container 51 that houses the charging / discharging unit 10, and an insulating cover 61 that insulates the positive electrode tab 11b and the negative electrode tab 12b. With this configuration, the insulating cover 61 can sufficiently insulate the container 51 from the positive electrode tab 11b. In particular, if the positive electrode tab 11b is configured to be long to ensure sufficient working space in order to facilitate welding of the positive electrode tab 11b to the positive electrode joint 21f, the positive electrode tab 11b may bend significantly inside the container 51 when the lid 52 is then attached to the container 51. Even if the positive electrode tab 11b is bent, the insulating cover 61 can sufficiently insulate the container 51 from the positive electrode tab 11b.

[0063] The positive electrode joint portion 21f of the positive electrode current collector plate 21 is formed in a triangular shape. With this configuration, stress is concentrated on the corners (tip portions) of the triangle shape of the positive electrode tab 11b and the positive electrode joint portion 21f, allowing them to come into contact with each other in a sufficiently tight fit. This allows the positive electrode joint portion 21f and the positive electrode tab 11b to be sufficiently joined.

[0064] The charge / discharge unit 10 is configured by winding a positive electrode 11 and a negative electrode 12 with a separator 13 interposed therebetween. As shown in the first embodiment, the battery 1 can be applied to a battery having a wound type charge / discharge unit 10.

[0065] In the manufacturing method of the battery 1, the positive electrode tab 11b and both ends of the convex positive electrode joint portion 21f of the positive electrode current collector plate 21 are pressed against each other using a first pressing member 501 and a second pressing member 502. According to the manufacturing method of the battery 1 configured as described above, the positive electrode tab 11b and the positive electrode joint portion 21f can be brought into contact with each other in a sufficiently tight state without directly pressing the positive electrode tab 11b and the positive electrode joint portion 21f. As shown in FIG. 21 , when the negative electrode tab 12b is pressed along both ends of the negative electrode joint portion 22f (both ends in the Y-axis direction) while in contact with the negative electrode joint portion 22f, tension is applied to the negative electrode tab 12b in both the positive and negative directions of the Y-axis centered on the negative electrode joint portion 22f. As a result, the negative electrode tab 12b and the negative electrode joint portion 22f of the negative electrode current collector plate 22 are brought into contact with each other in a tight state. This allows the positive electrode tab 11b and the positive electrode joint portion 21f to be sufficiently welded together.

[0066] The effects of the first embodiment have been described above using the configuration of welding between the positive electrode tab 11b and the positive electrode current collector plate 21. In the first embodiment, the effects of welding between the negative electrode tab 12b and the negative electrode current collector plate 22 are similar to the effects of welding between the positive electrode tab 11b and the positive electrode current collector plate 21 described above.

[0067] (Configurations and Effects of Modifications 1 to 3 of Battery 1 of First Embodiment) The joints of the current collector plates of Modifications 1 to 3 of the battery 1 of the first embodiment will be described with reference to Figs. 13 to 15. Below, we will describe the modified positive electrode joint 21f of the positive current collector plate 21. The modified negative electrode joint 22f of the negative current collector plate 22 is similar to the modified positive electrode joint 21f of the positive current collector plate 21, so the description will be omitted.

[0068] As shown in FIG. 13 , the joint portion 23f of the positive current collector plate 23 is formed in a trapezoidal shape that protrudes in the negative Z-axis direction, with the portion in contact with the first base portion 23a as the base. The cross section of the joint portion 23f in the Y-axis direction and the Z-axis direction is a trapezoid that tapers toward the negative Z-axis direction, and the joint portion 23f extends in the X-axis direction. The tip of the joint portion 23f is formed in a plane parallel to the first base portion 23a, and both ends in the Y-axis direction are formed in an inclined surface that slopes toward the first base portion 23a. With this configuration, the flat portion at the tip of the joint portion 23f can ensure a sufficient welding area with the positive electrode tab 11b, and the joint portion 23f and the positive electrode tab 11b can be sufficiently joined.

[0069] As shown in FIG. 14 , the joint portion 24f of the positive current collector plate 24 is formed in an arc shape that protrudes in the negative Z-axis direction, starting from the portion where the joint portion 24f contacts the first base portion 24a. The joint portion 24f has an arc-shaped cross section in the Y-axis direction and the Z-axis direction, and extends in the X-axis direction. The joint portion 24f is formed in a semicircular shape from the first base portion 24a toward the tip that protrudes in the negative Z-axis direction. The joint portion 24f may be formed in a semi-elliptical shape or a semi-parabolic shape. With this configuration, the arc-shaped joint portion 24f can eliminate an inflection point at the contact portion with the positive electrode tab 11b, thereby sufficiently joining the joint portion 24f and the positive electrode tab 11b while suppressing the load applied to the positive electrode tab 11b.

[0070] As shown in FIG. 15 , the joint 25f of the positive current collector plate 25 is formed in an arc shape that protrudes in the negative direction of the Z axis from the portion where it contacts the first base 25a, and its tip is formed in a flat surface parallel to the first base 25a. The cross section of the joint 25f in the Y-axis direction and the Z-axis direction is an arc shape with a flat surface at the tip, and the joint 25f extends in the X-axis direction. With this configuration, the flat portion at the tip of the joint 25f can ensure a sufficient welding area with the positive electrode tab 11b, thereby ensuring sufficient joining of the joint 25f and the positive electrode tab 11b. Furthermore, with this configuration, the arc portion around the tip of the joint 25f can reduce the load applied to the positive electrode tab 11b.

[0071] [Second embodiment] (Configuration and manufacturing method of battery 2 of second embodiment) The configuration of the battery 2 will be described with reference to FIGS.

[0072] The battery 2 of the second embodiment is configured by bundling multiple electrode tabs. In the battery 2 of the second embodiment, the same components as those of the battery 1 of the first embodiment are assigned the same reference numerals, and their description is omitted. The second embodiment will be described mainly focusing on components that differ from the first embodiment. In the description of the manufacturing method for the battery 2 of the second embodiment, only the manufacturing steps specific to the battery 2 will be described, and a description of the manufacturing steps similar to those for general batteries will be omitted.

[0073] The battery 2 of the second embodiment differs from the battery 1 of the first embodiment in that it has a charging / discharging body 210 instead of the charging / discharging body 10. The charging / discharging body 210 has one side 210a from which a positive electrode tab 211b and a negative electrode tab 212b protrude, another side 210b facing the one side 210a, and an outer circumferential portion 210c located between the one side 210a and the other side 210b. The charging / discharging body 210 is configured as a wound type in which a positive electrode 211 and a negative electrode 212 are stacked with a separator 13 interposed therebetween and wound. A plurality of negative electrode tabs 212b are formed on the negative electrode 212. The negative electrode joint portion 22f has higher rigidity in the stacking direction (Z-axis direction) of the negative electrode tabs 212b and the negative electrode current collector plate 22 than the plurality of negative electrode tabs 212b in a bundled state. 23, the multiple negative electrode tabs 212b are bundled together and welded to the negative electrode joint portion 22f of the negative electrode current collector plate 22. The configuration of the multiple positive electrode tabs 211b is similar to the configuration of the multiple negative electrode tabs 212b.

[0074] The manufacturing method of the battery 2 of the second embodiment is the same as the manufacturing method of the battery 1 of the first embodiment. However, in the first step, the bundled negative electrode tabs 212b are brought into contact with the negative electrode joint portion 22f of the negative electrode current collector plate 22. Similarly, in the first step, the bundled positive electrode tabs 211b are brought into contact with the positive electrode joint portion 21f of the positive electrode current collector plate 21.

[0075] (Effects of Battery 2 of Second Embodiment) The effects of the battery 2 and the manufacturing method of the battery 2 will be described below. The effects relating to the welding of the negative electrode tab 212b and the negative electrode current collector plate 22 will be mainly described below. The effects relating to the welding of the negative electrode tab 212b and the negative electrode current collector plate 22 are similar to the effects relating to the welding of the positive electrode tab and the positive electrode current collector plate 21. In addition to the effects of the battery 1 of the first embodiment, the battery 2 has the following effects.

[0076] The bundled negative electrode tabs 212b are welded to the negative electrode joint 22f of the negative electrode current collector plate 22. Even with this configuration, all of the negative electrode tabs 212b can be directly or indirectly welded to the negative electrode joint 22f without creating gaps between adjacent negative electrode tabs 212b. That is, because the negative electrode joint 22f, which is the welded region, protrudes from the negative electrode current collector plate 22, it is easier to bring all of the negative electrode tabs 212b into close contact with the negative electrode joint 22f directly or indirectly compared to conventional cases in which the welded region does not protrude from the negative electrode current collector plate. This allows sufficient electrical conduction between all of the negative electrode tabs 212b and the positive electrode joint 22f.

[0077] The negative electrode joint portion 22f of the negative electrode current collector plate 22 has higher rigidity in the stacking direction (Z-axis direction) of the negative electrode tabs 212b and the negative electrode current collector plate 22 than the bundled negative electrode tabs 212b. With this configuration, even if the multiple negative electrode tabs 212b are bundled, all of the multiple negative electrode tabs 212b can be deformed to conform to the shape of the negative electrode joint portion 22f of the negative electrode current collector plate 22 and welded in a state of being in close contact with the negative electrode joint portion 22f directly or indirectly. Therefore, sufficient electrical conduction can be achieved between all of the negative electrode tabs 212b and the negative electrode current collector plate 22.

[0078] The effects of the second embodiment have been described above using the configuration of welding the bundled negative electrode tabs 212b to the negative electrode current collector plate 22. In the second embodiment, the effects of welding the bundled positive electrode tabs to the positive electrode current collector plate 21 are similar to the effects of welding the bundled negative electrode tabs 212b to the negative electrode current collector plate 22 described above.

[0079] [Third embodiment] (Configuration and manufacturing method of battery 3 of third embodiment) The configuration of the battery 3 will be described with reference to FIGS.

[0080] The battery 3 of the third embodiment is configured as a laminated type in which the charging / discharging body 310 is not wound. In the battery 3 of the third embodiment, the same components as those of the battery 1 of the first embodiment are assigned the same reference numerals, and their explanations are omitted. The third embodiment will be described mainly with respect to components different from the first embodiment. In the explanation of the manufacturing method of the battery 3 of the third embodiment, only the manufacturing steps specific to the battery 3 will be described, and explanations of manufacturing steps similar to those for general batteries will be omitted.

[0081] The battery 3 of the third embodiment differs from the battery 1 of the first embodiment in that it has a charging / discharging body 310 instead of the charging / discharging body 10. The charging / discharging body 310 has one side 310a from which a positive electrode tab 311b and a negative electrode tab 313b protrude, another side 310b facing the one side 310a, and an outer periphery 310c located between the one side 310a and the other side 310b. The charging / discharging body 310 is configured as a laminated type in which a positive electrode 311 and a negative electrode 312 are stacked with a separator 313 interposed therebetween. The charging / discharging body 310 is configured by stacking multiple positive electrodes 311, separators 313, negative electrodes 312, and separators 313, each of which is formed in a rectangular shape, in this order. Each positive electrode 311 is formed with one positive electrode tab 311b. One negative electrode tab 312b is formed on each negative electrode 312. The negative electrode joint 22f has higher rigidity in the stacking direction (Z-axis direction) of the negative electrode tabs 312b and the negative electrode current collector plate 22 than the multiple negative electrode tabs 312b in a bundled state. As shown in Fig. 25, the multiple negative electrode tabs 312b are welded to the negative electrode joint 22f of the negative electrode current collector plate 22 in a bundled state. The configuration of the multiple positive electrode tabs 311b is the same as the configuration of the multiple negative electrode tabs 312b.

[0082] As a modified example of the charge / discharge body 310, a stacked type can be applied in which a single long separator is used and multiple short positive electrodes and multiple short negative electrodes are alternately arranged facing each other with the separator interposed therebetween. This modified example is a so-called Z-fold stacked type. In a charge / discharge body configured in this manner, the separator is folded and stacked, so that the positive electrodes and negative electrodes face each other with the separator interposed therebetween.

[0083] The manufacturing method of the battery 3 of the third embodiment is similar to the manufacturing method of the battery 1 of the first embodiment. However, in the first step, the bundled positive electrode tabs 311b are brought into contact with the positive electrode joint portion 21f of the positive electrode current collector plate 21. Similarly, in the first step, the bundled negative electrode tabs 312b are brought into contact with the negative electrode joint portion 22f of the negative electrode current collector plate 22.

[0084] (Effects of Battery 3 of Third Embodiment) The effects of the battery 3 of the third embodiment will be described. The battery 3 of the third embodiment includes a stacked charging / discharging body 310 configured by stacking a positive electrode 311 and a negative electrode 312 with a separator 313 interposed therebetween. The charging / discharging body 310 is configured by stacking multiple rectangular positive electrodes 311, separators 313, and negative electrodes 312 in this order: separator 313, negative electrode 312, separator 313. That is, the battery 3 of the third embodiment is configured by bundling multiple electrode tabs together, similar to the battery 2 of the second embodiment. Even with this configuration, all of the multiple electrode tabs and their joints can be directly or indirectly welded without creating gaps between adjacent electrode tabs. This allows sufficient electrical continuity between all of the multiple electrode tabs and their joints.

[0085] [Fourth embodiment] (Configuration and manufacturing method of battery 4 of the fourth embodiment) The configuration of the battery 4 will be described with reference to FIGS.

[0086] The battery 4 of the fourth embodiment is configured by arranging two charging / discharging bodies 410 side by side. In the battery 4 of the fourth embodiment, the same components as those of the battery 1 of the first embodiment are assigned the same reference numerals, and their description is omitted. The fourth embodiment will be described mainly with respect to components different from the first embodiment. In the description of the manufacturing method of the battery 4 of the fourth embodiment, only the manufacturing steps specific to the battery 4 will be described, and a description of the manufacturing steps similar to those for general batteries will be omitted.

[0087] The battery 4 of the fourth embodiment differs from the battery 1 of the first embodiment in that it has two charge / discharge bodies 410 instead of the charge / discharge body 10. The charge / discharge body 410 has one side 410a from which a positive electrode tab 411b and a negative electrode tab 412b protrude, the other side 410b facing the one side 410a, and an outer periphery 410c located between the one side 410a and the other side 410b. The two charge / discharge bodies 410 are aligned in the short-side direction (Y-axis direction) of the battery 4. The two charge / discharge bodies 410 are, for example, electrically connected in parallel. The charge / discharge body 410 is configured as a wound type in which a positive electrode 411 and a negative electrode 412 are stacked and wound with a separator 413 interposed therebetween. The positive electrode 411 has multiple positive electrode tabs 411b formed thereon. The negative electrode 412 has multiple negative electrode tabs 412b formed thereon. The positive electrode current collector plate 121 and the negative electrode current collector plate 122 of the current collector 120, the positive electrode terminal 141 and the negative electrode terminal 142 of the external terminal 140, the container and the lid 152 of the exterior body 150, the negative electrode side first insulating plate 163 of the insulator 160, etc., and the sealing body are configured to be longer in the short side direction (Y-axis direction) than the battery 1. With this configuration, each component of the battery 4 is matched to the size of the two charging / discharging bodies 410 arranged side by side along the short side direction (Y-axis direction) of the battery 4.

[0088] For example, two negative electrode joint portions 122f are formed on the negative electrode current collector plate 122, spaced apart in the short-side direction (Y-axis direction) of the battery 4. Each negative electrode joint portion 122f is formed in a triangular shape. Each negative electrode joint portion 122f faces the charging / discharging body 410 and extends in the longitudinal direction (X-axis direction) of the charging / discharging body 410. The multiple negative electrode tabs 412b provided on each of the two charging / discharging bodies 410 are bundled and joined to one of the two negative electrode joint portions 122f formed on the negative electrode current collector plate 122 that is located relatively close. The joint configuration of the positive electrode current collector plate and the multiple positive electrode tabs 411b is the same as the configuration of the negative electrode current collector plate 122 and the multiple negative electrode tabs 412b.

[0089] The manufacturing method of the battery 4 of the fourth embodiment is the same as the manufacturing method of the battery 1 of the first embodiment. However, in the first step, the bundled negative electrode tabs 412b are brought into contact with either one of the negative electrode joint portions 122f formed on the negative electrode current collector plate 122. Similarly, in the first step, the bundled positive electrode tabs 411b are brought into contact with either one of the negative electrode joint portions 122f formed on the positive electrode current collector plate 21.

[0090] (Effects of Battery 4 of Fourth Embodiment) The effects of the battery 4 of the fourth embodiment will be described. The battery 4 of the fourth embodiment has two wound-type charging / discharging bodies 410 arranged side by side in the short-side direction (Y-axis direction) of the battery 4. Here, for example, two negative electrode joint portions 122f are formed on the negative electrode current collector plate 122, spaced apart in the short-side direction (Y-axis direction) of the battery 4. Therefore, the multiple negative electrode tabs 412b provided on each of the two charging / discharging bodies 410 can be bundled and joined to one of the two negative electrode joint portions 122f formed on the negative electrode current collector plate 122 that is located relatively close to the other. The positive electrode current collector plate also has the same effects as the negative electrode current collector plate 122 described above.

[0091] As a modification of the fourth embodiment, three or more charge / discharge elements may be arranged in the short-side direction (Y-axis direction) of the battery 4. In this case, three or more joints are formed on the current collector plate at intervals in the short-side direction (Y-axis direction) of the battery.

[0092] The battery of the present invention is not limited to the configurations described in the embodiments, but can be configured appropriately based on the contents described in the claims.

[0093] The battery of the present invention is not limited to a lithium-ion battery. The battery of the present invention can be applied to, for example, a nickel-metal hydride battery or a lead-acid battery. The battery of the present invention is not limited to a secondary battery. The battery of the present invention can be applied to a primary battery. Each embodiment has been described in detail or simply to clearly explain the present invention, and it is not necessary to include all of the components described, or components not shown may be included. Furthermore, some of the components of one embodiment may be deleted, replaced with components of another embodiment, or combined with components of another embodiment. [Explanation of symbols]

[0094] 1, 2, 3, 4 Battery, 10, 110, 210, 310, 410 Charge / discharge body, 11, 111, 211, 311, 411 Positive electrode (electrode), 11S Positive electrode current collector (current collector), 11b Positive electrode tab (electrode tab), 11c Side edge, 12, 212, 312, 412 Negative electrode (electrode), 12S Negative electrode current collector (current collector), 12b Negative electrode tab (electrode tab), 12c Side edge, 21 Positive electrode current collector (current collector), 21f Positive electrode joint (joint), 22 Negative electrode current collector (current collector), 22f Negative electrode joint (joint), 51 Container, 61 Insulating cover (insulator), 122 Negative electrode current collector (current collector), 122f Negative electrode joint (joint), 501 first pressing member (pressing member), 502 second pressing member (pressing member), L1 laser light.

Claims

1. A rectangular container; A charge / discharge body accommodated in the container; a lid for sealing the opening of the container; Equipped with external terminals are provided on both ends of the upper surface of the lid in the longitudinal direction, a rectangular current collecting plate supported by the lid facing the charge / discharge body and connected to the external terminal; A battery, The charge / discharge body includes an electrode tab protruding toward the current collector plate, The current collecting plate includes a base portion and a joint portion formed in the longitudinal direction from the base portion and convex downward, the electrode tab is deformed from a direction in which it protrudes from the charging / discharging body to a direction in which it faces the joint portion so that the width direction of the electrode tab is aligned with the longitudinal direction of the joint portion, and is pressed against the joint portion, and the electrode tab and the joint portion are welded together. battery.

2. The electrode tab and at least a tip of the joint are welded. The battery of claim 1 .

3. the joint portion has higher rigidity than the electrode tab in the stacking direction of the electrode tab and the current collector plate; The battery according to claim 1 or 2.

4. the bundled electrode tabs and the joint portion are welded together; The battery according to any one of claims 1 to 3.

5. the joint portion has higher rigidity in a stacking direction of the electrode tab and the current collecting plate than the bundled plurality of electrode tabs; The battery of claim 4.

6. The electrode tab and the joint portion are welded by laser light. The battery of any one of claims 1 to 5.

7. The electrode tab is formed to protrude from a side edge of the current collecting layer of the charge / discharge body. The battery of any one of claims 1 to 6.

8. The joint portion has any one of a triangular shape, a trapezoidal shape, an arc shape, and an arc shape having a flat portion at its tip. The battery of any one of claims 1 to 7.

9. The charge / discharge body is configured by winding or stacking a positive electrode and a negative electrode with an insulating member interposed therebetween. The battery of any one of claims 1 to 8.

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